The present invention relates to a fluid transfer device for transferring fluid to or from a patient, and more particularly to a fluid transfer device having a retractable needle.
Various types of medical devices employ a needle for piercing the skin of a patient for diagnostic or therapeutic purposes. One such fluid transfer device is a fluid collection device which includes a needle for piercing a blood vessel or other part of the patient to allow a fluid, for example, blood, to be sampled from a patient. When the needle is inserted into the patient, blood or other fluid is withdrawn through the needle, for example, into a vacuum collection tube. Handling of such needle-bearing medical devices after the needle is withdrawn from the patient can result in transmission of various pathogens, most notably human immune virus (HIV), thereby exposing medical personnel and possibly others to serious or fatal illness due to an inadvertent needle stick or scratch.
After use of a needle-bearing medical device, it is desirable to have an easily usable feature for retracting the needle into a housing to avoid contact with the small volume of contaminated fluid or blood that may remain on or inside the needle. It is further desirable that it be made difficult for personnel to accidentally or intentionally re-extend the needle from within the housing.
Accordingly, there is a need for a fluid transfer device that not only retracts the needle following its use, but that also captures or positively retains the needle in the retracted position within the housing thereafter.
In light of the foregoing, the present invention provides a medical device having a hollow housing and a needle with a sharpened tip. The needle is operable between an extended and a retracted position. The sharpened tip projects forwardly from the housing in the extended position and the sharpened tip is enclosed within the housing in the retracted position. A biasing element biases the needle toward the retracted position. A needle retainer releasably retains the needle in the extended position. An actuator actuates the needle retainer to release the needle so that the biasing element propels the needle rearwardly toward the retracted position. A rearward stop connected with the needle is operable to retain the needle against continued rearward displacement after the needle is retracted. A forward stop connected with the needle is operable to retain the needle against forward displacement after the needle is retracted.